1. Field of the Invention
The present invention relates to the administering of live, probiotic anaerobic bacteria to livestock. More particularly, it relates to a method and apparatus for preparing, containing and preserving the viability of an aqueous suspension of said bacteria as a concentrated, homogeneous suspension under controlled-temperature conditions at a feedlot location until time for addition of a diluted portion thereof to animal feed, whereby said bacteria can be regularly administered to large numbers of animals in an efficient manner.
2. General Discussion of the Background
It has long been a common practice to administer chemical additives to cattle and other livestock to supplement feed rations, thereby providing a balanced diet, protecting the animals from disease, and stimulating growth. Such additive supplements, commonly termed microingredients, usually should be administered to each animal on a regular basis in carefully controlled dosages to ensure optimal benefit. Individual dosages are typically small due to the high potency of microingredients.
A number of methods and apparatuses have been devised for accurately dispensing, at the feedlot, separately stored livestock feed additive chemical concentrates into a volume of fluent carrier material, such as water, for dilution, dispersion, and suspension, and for transporting the resulting slurry into livestock drinking water or feed rations shortly before the time of intended consumption. These methods and apparatuses are disclosed in U.S. Pat. Nos. 3,437,075; 3,498,311; 3,670,923; 3,806,001; 3,822,056; and 4,733,971, the disclosures of which are incorporated herein by reference.
Additive supplements can also include specific live microorganisms. For example, administration of certain live probiotic bacteria can help restore optimal intestinal flora in animals such as cattle, especially after stressful situations such as transport to a feedlot. Gedek, B., "Probiotics in Animal Feeding--Effects on Performance and Animal Health," Feed Magazine, November 1987. With regular administration, probiotic bacteria also increase nutrient absorption efficiency and help control the proliferation of harmful microorganisms in the animals' digestive tracts that could otherwise cause disease conditions adversely affecting rates of animal development and weight gain. A bacterial species commonly administered to cattle for such purposes is Lactobacillus acidophilus, an anaerobic, lactic acid producer. Klaenhammer, T. R. (1982) "Microbiological Considerations in Selection and Preparation of Lactobacillus Strains for Use as Dietary Adjuncts," J. Dairy Sci 65:1339-1349. An example of such a product is "Cobactin," a lyophilized L. acidophilus formulation from Biotechniques Laboratories, Inc., Redmond, Wash.
Anaerobic bacteria are adversely sensitive to environmental influences such as oxygen, moisture, temperature extremes, and many chemicals. Until recently, the bacteria were mixed with dry, diluting filler material and other additive supplements as a premix. However, animal weight-gain results obtained with such bacteria-containing premixes were inconsistent because large numbers of bacteria died in the premix before addition to feed due to improper formulation, packaging and storage of the premix. At least one manufacturer of bacterial supplements has partially overcome these problems by lyophilizing the bacteria in the absence of chemical microingredients and packaging the dry bacteria in hermetically sealed packets under an inert, arid atmosphere such as dry nitrogen. These advances greatly extend the shelf-life of commercially packaged anaerobic bacterial formulations., However, even properly packaged anaerobic bacteria become labile due to contact with air and moisture the moment the package is opened. Therefore, such packaging still does not solve the problem of maintaining the bacteria in a live state and delivering them to large numbers of animals in proper dosages after the package is opened. Without some means of extending viability, anaerobic bacteria from an opened package must be properly diluted and presented to the animals within a very short time after opening the package, which is time prohibitive and impractical in large feedlots. Hence, there is still a need for a method and apparatus for preserving bacteria, after opening the package, in a ready-to-use viable condition at a known concentration that can be delivered at the correct dosages efficiently on a regular basis to large numbers of animals.
There are several known methods used to administer bacteria from a dry concentrate to animals, but the existing methods have significant drawbacks. One known method is to rehydrate the dry bacteria in dilute aqueous suspension and administer the suspension orally via drenching. However, drenching is so cumbersome and time-prohibitive that it is usually only performed during times of critical need, such as immediately after the animals arrive at the feedlot or when an animal is obviously sick.
A second known method is to manually sprinkle dried bacteria onto animal feed in the feed bunks, which is time-prohibitive in large feedlots. Also, to attain more uniform distribution, appreciable predilution of the concentrated bacteria with dry filler material is required, which causes appreciable loss of bacterial viability resulting from contact with concentrated substances. Furthermore, it is practically impossible via this method to ensure that each animal receives a correct and consistent dose when many animals feed from the same bunk.
A third known method is to mix the dry bacteria with feed before distribution to the feed bunks. This method is undesirable because homogeneity of such a mixture is very difficult to attain and because large numbers of bacteria are killed by the time the mixture is presented to the animals.
Accordingly, there remains no known practical method or apparatus for accurately administering regular, small dosages of probiotic bacteria to livestock on a large scale, despite the need for such a method and apparatus.
Heretofore, the aforementioned methods and apparatuses for regularly administering chemical microingredients in small, accurate dosages to livestock on a large scale in a liquid carrier slurry through their feed rations have been thought to be inapplicable to live, anaerobic bacteria of the class described because of the lack of any method or means for storing the bacterial additive in a form that would maintain the viability of the bacteria and yet be usable in such prior methods and apparatuses. More specifically, to be applicable to such prior methods and apparatuses, the live bacteria would need to be stored for prolonged periods of time in dry particulate or liquid form in a known, constant concentration at a feedlot for immediate dispensing by weight or volume, on demand. As a result, despite general knowledge of the benefits of regular administration of probiotics to certain livestock, feedlot operators have not done so because of inadequate methods and lack of a suitable apparatus.
Hence, there is a need for a method and apparatus for: (a) preparing and storing at the feedlot a homogeneous volume of bacterial material, at known concentration and ready for on-demand use, where the bacteria are preserved in a viable state until immediately before presentation to the animals and in a form conducive to accurate dispensing by weight or volume; and (b) feeding the bacteria in a live condition to large numbers of livestock on a regular basis such that each animal receives a correct dosage of live bacteria, preferably mixed with its feed, and with other microingredients as required.
Accordingly, a primary object of the present invention is to provide a method and apparatus for delivering a known dosage of desired live bacteria mixed with animal feed to large numbers of livestock for ingestion on a regular basis.
Another primary object is to provide a method and apparatus for preserving and storing at a feedlot location a known concentration of a liquid suspension of desired bacteria in live form for prolonged periods in a condition for immediate, on-demand use for administration to animals.
Another primary object is to provide a method and compact apparatus for preparing and storing a concentrated volume of aqueous liquid suspension of live, probiotic bacteria at known concentration at an animal feedlot location, and for preserving said bacteria in a viable condition at a known, stable concentration until time for adding a known mass or volume thereof to animal feed.
Another primary object is to provide a method and apparatus as aforesaid for preparing and storing a concentrated volume of aqueous, liquid suspension of live probiotic bacteria and for preserving said bacteria in a viable condition at a known, stable concentration until time for removing a known mass or volume thereof for further dilution and addition of other microingredients before adding to a known mass or volume of animal feed. Another primary object is to provide a method and apparatus for delivering said concentrated bacterial liquid suspension to a gravimetric or volumetric measuring device to accurately dispense a preselected mass or volume, respectively, of the concentrated bacterial liquid suspension to a known mass or volume of aqueous liquid containing other microingredient additives, which is subsequently added to a known mass of livestock feed ration just before the feed ration is presented to the animals for consumption.
Another primary object is to provide a method and apparatus for preparing and storing a concentrated volume of aqueous, liquid suspension of live probiotic bacteria and for preserving said bacteria in a viable condition at a known, stable concentration until time for removing a known mass or volume thereof for further dilution and addition of other microingredients before therapeutically administering to animals via other methods such as drenching.
Another primary object is to provide a method and apparatus as aforesaid that adjust the temperature of the concentrated bacterial liquid suspension to within a preselected range for optimal bacterial survival in a viable condition at a known, stable concentration and regulate said temperature within that range uniformly throughout the volume of concentrated bacterial liquid suspension.
Another primary object is to provide a method and apparatus that insulate the concentrated bacterial liquid suspension contained within said apparatus from changes in ambient temperature.
Another primary object is to provide a method and apparatus as aforesaid that keep the concentrated bacterial liquid suspension contained therein uniform with respect to concentration of bacteria.